The Study of the Key Successful Factors for Concrete Aggregate Quality Management-the River Gravel as an Example

Autor: LIN,WEN-SHENG, 林文盛
Rok vydání: 2019
Druh dokumentu: 學位論文 ; thesis
Popis: 107
Ready-mixed concrete is one of the most used material in all sort of domestic constructions up to now. The quality of the ready-mixed concrete determines the structural properties, in turn, the safety and the expected lifetime of the building. Construction companies not only request the products that meet the standards, but also choose their suppliers based on the lower price. Facing the vicious price competition, the ready-mixed producers come to a dilemma between cost reduction and quality improvement. Thus, this research aims to analyze how ready-mixed producers identify key factors that influence the quality, among the materials, processing, and blending of gravel, and through the analysis, to understand the quality and properties of river gravel in relevant regions. In this study, an analysis was performed to pinpoint the factors affecting the quality of ready-mixed concrete, based on the secondary data collected from the industry and the case study of practices in Zhuoshui River. The result indicates that the gravels are consist of different material and display different stiffness, depending on the origin in Taiwan, making most of the materials in ready-mixed concrete uncontrollable in its quality. Therefore, sample testing is required for ready-mixed products to meet the standards in national regulations. However, when the practice of producing ready-mixed concrete raise above the standards, the quality can be substantially different. For example, gravel products that go through disintegration and washing, blending water, cement, and other cementitious material, are those that are more controllable. On the other hand, in the processes of producing ready-mixed concrete, the testing; choosing of material, sampling and analyzing, grading and mixing, test blending, slump test, cylindrical specimens production and curing, the construction; transport onsite by the agitating lorry, blending, pumping, pouring, ramming, and curing, can all play a part in determining the quality of the concrete.
Databáze: Networked Digital Library of Theses & Dissertations